KR20140040674A - Container for nonaqueous electrolyte solution, nonaqueous electrolyte solution to put in container, and method for storing nonaqueous electrolyte solution - Google Patents

Abstract

(1) A container made of a material containing an aluminum or aluminum alloy layer, and filled with a nonaqueous electrolyte solution in which an electrolyte salt is dissolved in a nonaqueous solvent, the resin having a lid and an intermediate cap, and storing the container. It is a container for nonaqueous electrolyte which keeps the water content of the nonaqueous electrolyte solution after 50 days or less, (2) the nonaqueous electrolyte solution contained in the container, and (3) the nonaqueous electrolyte storage method. The container for nonaqueous electrolyte is a lightweight container that can prevent decomposition during storage of the nonaqueous electrolyte, maintain high quality, and can easily and reliably handle the nonaqueous electrolyte.

Description

CONTAINER FOR NONAQUEOUS ELECTROLYTE SOLUTION, NONAQUEOUS ELECTROLYTE SOLUTION TO PUT IN CONTAINER, AND METHOD FOR STORING NONAQUEOUS ELECTROLYTE SOLUTION}

The present invention relates to a container for a nonaqueous electrolyte, a method for storing a nonaqueous electrolyte and a nonaqueous electrolyte in a container.

Background Art In recent years, electrochemical devices, particularly lithium secondary batteries, have been widely used as power sources for electronic devices such as mobile phones and notebook computers, power sources for electric vehicles, and power storage.

The lithium secondary battery is mainly composed of a positive electrode, a negative electrode, and a nonaqueous electrolyte composed of a lithium salt and a nonaqueous solvent containing a material capable of occluding and releasing lithium. Examples of the nonaqueous solvent include cyclic carbonate, chain carbonate, and chain carboxylic acid. Organic solvents, such as ester, lactone, and ether, are used.

The said non-aqueous electrolyte solution was preserve | saved and used conventionally in the container made of stainless steel for the purpose of the corrosion prevention of the container at the time of storage. However, stainless steel containers have a problem that they are difficult to handle because of their high mass, and are difficult to reduce in size due to workability problems. In addition, since the lid is also made of stainless steel in the conventional stainless steel container, when the liquid falls during use, solid content precipitates in the screw portion of the container aperture, which requires a great force to open and close the lid, and promotes deterioration of the nonaqueous electrolyte. There was also a problem. For this reason, there has been a demand for a container for corrosion resistance, light weight, and good handleability and an electrolyte solution.

As a container for storing the non-aqueous electrolyte, Patent Document 1, for example, seals the fuselage part with a thin film portion formed at the end of the container cylinder for the purpose of improving the corrosion resistance and seal function, and tears the thin film portion. The polyethylene resin container which opens and closes a fuselage part and uses is disclosed by this. However, in this container, the sealing property of the container cannot be secured after opening and closing once.

Patent Literature 2 discloses an electrolytic solution container formed by sealing a pouring hole with a rubber cap, but the sealing property of the pouring hole is insufficient.

Examples of Patent Document 3, the cyclic carbonate and chain carbonate, a secondary battery non-aqueous and is an electrolyte is disclosed, wherein the non-aqueous stainless electrolyte vessel non-aqueous containing specific die siloxane in the LiPF ₆ is dissolved in a non-aqueous electrolyte in a solvent containing It is described that it was sealed to and stored for 30 days. However, since the electrolyte is usually handled in a narrow space such as a glove box, there is a problem that a heavy stainless container is difficult to handle.

On the other hand, in a can container containing a beverage, cooking oil, or the like as a liquid solution, a so-called reciprocal seal which is provided with a caliber that can be engaged with a sealing cap, and which is capable of being attached to and detached from the caliber can be sewn. (reseal) cans are known. Such a sealing can is molded by a thin metal plate such as an aluminum alloy plate or a stainless steel plate, but in general, when a chemical product is used as the liquid solution, the sealing function of the container opening is insufficient.

Japanese Utility Model Publication Hei 5-31814 Japanese Utility Model Publication No. 56-51260 Japanese Patent Publication No. 2010-92748

Conventionally, considering the strength of a stainless steel plate and the corrosiveness of aluminum, it was thought that changing the material of the container for nonaqueous electrolyte from a stainless steel plate to aluminum is not considered at all.

The present invention provides a container for a nonaqueous electrolyte, a method for storing a nonaqueous electrolyte and a nonaqueous electrolyte, which can prevent decomposition during storage of the nonaqueous electrolyte, maintain high quality, and can easily and reliably handle the nonaqueous electrolyte. It is a task to do it.

In the case of the known container, for example, a container made of stainless steel, since the weight of the container is heavy, there is a problem that a force is required when handling in a narrow space such as a glove box, and the work efficiency is lowered. Moreover, while repeating opening and closing of a lid, electrolyte deposits accumulate between a lid and a container main body, the force is needed for opening and closing of a lid, and there existed a problem that handleability fell.

MEANS TO SOLVE THE PROBLEM The present inventors examined the storage performance with respect to the nonaqueous electrolyte solution of the conventionally well-known container in detail, and, as for the said well-known container, sufficient corrosion resistance cannot be ensured after opening and closing once, It turned out that it cannot be used as a storage container.

Thus, the inventors of the present invention have studied to solve the above problems, and as a result, the container for nonaqueous electrolyte composed of aluminum or aluminum alloy is configured to maintain the moisture content at the time of storage of the nonaqueous electrolyte at 50 ppm or less, thereby making it light and handleable. It was found that this was excellent and that the quality of the nonaqueous electrolyte solution could be maintained, thus completing the present invention.

That is, this invention provides following (1)-(3).

(1) A container made of a material containing an aluminum or aluminum alloy layer, and filled with a nonaqueous electrolyte solution in which an electrolyte salt is dissolved in a nonaqueous solvent, the resin having a lid and an intermediate cap, and storing the container. A container for nonaqueous electrolytes, which maintains the water content of the nonaqueous electrolyte solution after 50 days or less.

(2) A nonaqueous electrolyte in which a nonaqueous electrolyte solution in which an electrolyte salt is dissolved in a nonaqueous solvent is filled into a container, wherein the container is made of a material containing an aluminum or aluminum alloy layer, and the lid and the middle cap of the container are made of resin. The nonaqueous electrolyte solution which contained in the container whose water content of the nonaqueous electrolyte solution 30 days after the said container storage is maintained at 50 ppm or less.

(3) A method of preserving a nonaqueous electrolyte solution for storing a nonaqueous electrolyte solution in a container, wherein the container is made of a material containing an aluminum or aluminum alloy layer, and the lid and the middle cap of the container are made of resin, and the container is stored. The storage method of a nonaqueous electrolyte solution which keeps the water content of the nonaqueous electrolyte solution after 50 days or less.

According to the present invention, a lightweight nonaqueous electrolyte container, a nonaqueous electrolyte solution and a nonaqueous electrolyte solution, which can prevent decomposition during storage of the nonaqueous electrolyte solution, maintain high quality, and can easily and reliably handle the nonaqueous electrolyte solution. A preservation method can be provided.

The container for nonaqueous electrolyte of this invention is a container which preserves the nonaqueous electrolyte which melt | dissolves electrolyte salt in the nonaqueous solvent especially containing cyclic carbonate, and is 2 or more times, Preferably it is 3 times or more, More preferably, it is 5 times or more When the lid is opened and closed and repeatedly used, it is possible to prevent decomposition of the nonaqueous electrolyte during storage, to maintain high quality, and to be lightweight and excellent in handling.

1 is a schematic view showing an example of a can of the container for nonaqueous electrolyte of the present invention.
Fig. 2 is a schematic diagram showing an example of an intermediate plug and a lid of the container for nonaqueous electrolyte of the present invention. (a) shows an inner intermediate plug type, (b) an external intermediate plug type, and (c) shows a lid of a type in which an annular projection (intermediate plug) is placed.

The container for nonaqueous electrolyte solution of this invention is a container which consists of a material containing an aluminum or aluminum alloy layer, and fills the nonaqueous electrolyte solution which melt | dissolves electrolyte salt in a nonaqueous solvent, It has a resin lid and an intermediate stopper, It is characterized by maintaining the water content of the nonaqueous electrolyte solution after 30 days of container storage at 50 ppm or less.

Since the container for nonaqueous electrolyte of the present invention maintains the water content of the nonaqueous electrolyte after 50 days of container storage at 50 ppm or less, the container for nonaqueous electrolyte is formed of a material containing aluminum or an aluminum alloy layer and sealed with a resin lid and an intermediate plug. Consists of.

[Container for nonaqueous electrolyte solution]

As a material of the container for nonaqueous electrolyte of the present invention (hereinafter, also simply referred to as "container"), a material containing aluminum or an aluminum alloy layer is used from the viewpoint of corrosion resistance to the nonaqueous electrolyte filled in the container. Preferred is a material comprising a pure aluminum based material or an aluminum-manganese based alloy layer. The material containing aluminum or an aluminum alloy layer may be a material composed of aluminum or an aluminum alloy layer alone, or may be a material composed of a laminated structure with other layers.

In the case of the stainless container, when the electrolyte solution is taken out of the container, the liquid drops, and the electrolyte solution adheres to the screw portion of the container aperture, and it dries so that a solute such as an electrolyte salt contained in the electrolyte solution becomes a solid material. As a result, large rotational force was required when opening the lid, and it was necessary to open the lid using a tool. Since the lid opening of the electrolyte container is usually performed in a narrow space such as a glove box, improvement of workability in the field of testing and research has been required. Moreover, there existed a problem that a clearance gap was created by the solid substance precipitated between the lid of the container and the aperture part, and the deterioration of a nonaqueous electrolyte was accelerated.

On the other hand, the container for aluminum nonaqueous electrolyte solution of this invention can significantly reduce the container main body, and also, since the strength balance of the whole container is good, it became possible to use a lid for resin. As a result, even if there are some deposits on the screw portion of the container aperture part, the handleability is good for a long period of time without increasing the rotational force at the time of opening the lid, and it is possible to use repeatedly, and to prevent the deterioration of the nonaqueous electrolyte solution.

Furthermore, by strictly managing the moisture of the nonaqueous electrolyte, the corrosion resistance of the container made of a pure aluminum-based material or a material containing an aluminum-manganese alloy layer can be further improved.

As pure aluminum type material, since purity is 99% or more, since corrosion resistance is favorable, it is preferable, 99.5% or more is more preferable, 99.7% or more is more preferable. Specific examples of the pure aluminum-based material include 1050 (purity 99.50% or higher), 1060, 1070 (purity 99.70% or higher), 1080 (purity 99.80% or higher), 1085 (purity 99.85% or higher), and 1100 (purity 99.00) that are JIS 1000 series. % Or more), 1200 (purity of 99.00% or more), 1N00, etc. are mentioned suitably.

Further, aluminum-manganese alloys are more preferable as materials requiring strength because they have corrosion resistance and higher strength than pure aluminum.

The aluminum (Al) -manganese (Mn) -based alloy may be an Al-Mn binary alloy, or may be a ternary or higher Al-Mn- containing at least one additional element X such as copper, silicon, magnesium, or zinc. X alloy may be sufficient. In either case, the manganese content of the alloy is 0.2 to 10% by mass, preferably 0.5 to 5% by mass, preferably 0.8 to 3% by mass, from the viewpoint of strength and corrosion resistance.

As a specific example of aluminum-manganese alloy, 3003, 3004, 3005, 3104, 3105, 3203 etc. which are JIS 3000 series are mentioned suitably.

Aluminum or an aluminum alloy is formed in a container, or after polishing the surface of the container, and then left in air to form a natural oxide film, an oxide film is formed by an oxidizing agent, or a fluorinated film is formed. It is preferable to improve the corrosion resistance of a container by forming.

As an oxidizing agent which oxidizes the surface of aluminum or an aluminum alloy, the gas containing at least 1 sort (s) chosen from oxygen, ozone, nitrous oxide, and nitrogen peroxide, or mixed gas of those gases, and inert gas, such as nitrogen and argon, is mentioned. have.

Examples of the fluorinating agent that forms a fluorinated film on the surface of aluminum or an aluminum alloy include a gas containing at least one or more selected from fluorine, nitrogen fluoride, and chlorine trifluoride, or a mixed gas of those gases with an inert gas such as nitrogen or argon. Can be mentioned.

An oxide film or a fluoride film can be formed on the surface of a container by holding aluminum or an aluminum alloy in said gas or gas stream, for example for about 0.1 to 24 hours at the temperature of 100-600 degreeC.

Also for other aluminum alloys other than the aluminum-manganese alloy, a synthetic resin or the like having good corrosion resistance on the inner surface of the container can be coated and used. Examples of the synthetic resins include polyolefins such as polyethylene (PE) and polypropylene (PP), thermoplastic resins such as polyester such as polyethylene terephthalate (PET) and polyamide such as nylon (NY), and polytetrafluoroethylene. Fluorine resins, such as (Teflon (trademark)), an ethylene propylene dimer (EPDM), an ethylene propylene tetramer (EPT), a perfluoroelastomer, etc. are mentioned. Preferably the thickness is 5-50 micrometers, More preferably, it is 10-30 micrometers.

The shape of the container is not particularly limited, and may be any shape such as a bottle type, a cylindrical shape, an aluminum laminated paper bag type, an aluminum pouch type, or the like.

The bottle-shaped container can have an arbitrary cross-sectional shape in the horizontal direction of the container, such as a circle, a polygon such as a 3 to 8 octagon, or the like. Especially, it is preferable that the cross-sectional shape of a horizontal direction is circular from a viewpoint of the strength and workability of a container. It is also possible to continuously change the cross-sectional area in the vertical direction of the container. For example, by making the cross-sectional area near the center in the height direction of the container smaller than the vicinity of both ends, it is possible to form a concave structure in which a part of the container body (body) is tapered, or to give a concave-convex surface to the container to make it easy to hold the container. It may be.

The aluminum laminated paper bag-type container can be made into the shape of a foot-note in which the cross-sectional shape of the container in the horizontal direction was made into square or the like. It is preferable to make the structure of an aluminum laminated paper into the multilayered structure laminated | stacked in the order of resin layer 1 / aluminum or an aluminum alloy layer / resin layer 2 / paper layer / resin layer 3 from the surface side (inner side) which contact | connects a non-aqueous electrolyte solution. As resin layer 1, polyolefin layers, such as PE and PP, and / or polyester layers, such as PET, resin layer 2, and resin layer 3, polyolefin layers, such as PE and PP, are mentioned. Moreover, there is no restriction | limiting in particular in the paper used for a paper layer, Manila board paper, a white board paper, etc. which are used as a paper container paperboard are mentioned.

The aluminum pouch type container is preferably a multi-layered structure in which a resin layer such as polyolefin such as PP, polyester such as PET, polyamide such as NY, and an aluminum layer or an aluminum alloy layer are laminated, and a standing pouch. It is preferable to make ().

In these, a bottle type container is easy to handle and is suitable.

1 is a schematic view showing an example of a can body which is the main body of the bottle-shaped container of the present invention. The can body 1 has a disk-shaped bottom part (not shown), a cylindrical can body 2 whose lower end is joined to the periphery of the bottom part, and a skirt wall 4 provided at the top of the can body 2. And an aperture portion 5 provided on the skirt wall 4. A screw portion 6 is formed on the outer circumferential surface of the aperture portion 5, and a liquid injection hole 3 is formed in the upper edge portion of the aperture portion 5.

The can body 2 is, for example, bent a thin plate of aluminum or an aluminum alloy having a thickness of 0.2 to 1.0 mm, preferably 0.2 to 0.6 mm, more preferably 0.3 to 0.5 mm, with its overlapping edges. It can form by welding together and integrally joining. On the inner surface of the can body 2, the inner surface film which consists of synthetic resins can be formed as needed. The material of the inner surface coating is not particularly limited as long as it is a material without elution to the nonaqueous electrolyte.

The outer shape of the can body 2 has the linear shape set substantially constant over the full length. In the uppermost part of the can body 2, the aperture part 5 is formed through the skirt wall 4, and the upper edge part of the aperture part 5 becomes the injection hole 3. The injection hole 3 is sealed by an intermediate plug (not shown).

The skirt wall 4 has a tapered smooth cylindrical curved shape that becomes small in diameter upward along the central axis line of the can body 2. The angle of inclination of the skirt wall 4, that is, the angle to the line perpendicular to the center axis line of the can body 2, is preferably in the range of 20 to 50 °, more preferably in view of the mechanical strength of the can body 1. It may be set in the range of 25 to 45 °.

On the outer circumferential surface of the aperture portion 5, a male screw for screwing with a screw portion of a lid (not shown) is formed. In addition, a screw is not specifically limited, The screw which consists of the convex part or recessed part which winds the aperture part 5, or the screw which consists of protrusions or recessed grooves formed in discontinuously may be sufficient, and the number of screws is also arbitrary. In addition, instead of forming a male screw on the outer circumferential surface of the caliber portion 5, a female screw for screwing with a screw portion of a lid (not shown) may be formed on the inner circumferential surface of the caliber portion 5, in which case the lid A male screw threaded to the female screw formed on the inner circumferential surface of the aperture portion 5 is formed.

The container for nonaqueous electrolyte of the present invention is covered with a lid to seal and store the internal nonaqueous electrolyte, but the airtightness of the container is more securely maintained, and the liquid leakage of the nonaqueous electrolyte solution filled in the container is more reliably prevented. In order to keep the quality of electrolyte solution high quality for a long time, and to maintain good handleability, an intermediate stopper is used.

That is, in order to maintain the water content of the non-aqueous electrolyte solution after 30 days of container storage at 50 ppm or less, Preferably, the acid content of the non-aqueous electrolyte solution after 30 days of container storage is converted into hydrogen fluoride (HF) as described later. In order to maintain 50 ppm or less, and to maintain the change in acid content of the non-aqueous electrolyte solution up to 30 days after container storage within ± 20 ppm in terms of HF, and to maintain the APHA of the non-aqueous electrolyte solution to 50 or less, In order to maintain the material of the lid and the middle plug, it can determine the structure of the aperture (5).

2 is a schematic view showing an example of a lid and an intermediate plug of the container for nonaqueous electrolyte of the present invention. (a) shows the inner stopper type, (b) the outer stopper type, and (c) shows the lid of the annular projection part (intermediate stopper).

 As shown in Fig. 2, the intermediate stopper may be separated from the lid, and may be an internal stopper 7 fitted inside the injection hole or an external stopper 8 inserted outside the injection hole. have. Since the external intermediate plug 8 has less chance of contacting the non-aqueous electrolyte solution and the intermediate plug than the internal intermediate plug 7, it is preferable to maintain the sealing property more easily. In addition, it is preferable to attach a handle or the like for easy removal to the middle plug.

In the case where the intermediate stopper is the inner stopper 7, when the inner stopper 7 is inserted into the injection hole, the outer diameter of the end portion of the side of the inner intermediate stopper 7 in contact with the inside of the injection hole is the inside diameter of the injection hole. It may be inclined so as to be smaller than that. In addition, the end portion may be notched or curved, which is preferable because the inner intermediate plug 7 is easily inserted into the injection hole.

As shown in Fig. 2 (c), the intermediate plug may be in the form of an annular projection attached to the lid, and may be integrated with a lid that can be sealed in contact with the inner wall of the pouring hole when the lid is closed. . By providing the lid 9 in which the annular projection part (intermediate stopper) is provided, the sealing property of a container can be improved and the volatilization of the low boiling point solvent contained in a nonaqueous electrolyte solution, and mixing of the water outside the container can be prevented more effectively. The annular protrusion provided on the lid is preferably provided so that the surface (outer wall) in contact with the inner wall of the pouring hole is inclined with respect to the inner wall of the pouring hole, and the inclination angle θ is preferably 0.5 to 45 °, and preferably 1 to 30 °. Is more preferable.

Opportunity for the lid to contact the nonaqueous electrolyte in the inner intermediate stopper 7 or the outer intermediate stopper 8 in which the intermediate stopper and the lid are separated from the lid 9 in which the annular protrusion (intermediate stopper) is placed. Since there is little, since it is easy to maintain sealing more, it is preferable.

The pouring hole of a container can be made into the ordinary which has an outer diameter smaller than the trunk diameter of a container. Moreover, a notch and a recess can be provided in a normal liquid injection hole, and it can also be set as the shape which is hard to spill liquid.

In addition, by providing an annular liquid spill prevention member that is applied to a commercially available preservation bottle (Duran® bottle, etc.), after the electrolyte is poured, the electrolyte can be prevented from flowing down to the opening of the container or the screw. have.

The ratio of the size of the injection hole and the intermediate plug is (inner diameter of the injection hole / outer diameter of the intermediate plug) in the case of the circular lid and the internal intermediate plug, (inside diameter of the intermediate plug) The ratio of the outer diameter of the pouring hole is preferably 0.920 to 0.995, respectively. 0.940 or more are more preferable, as for the minimum of the said dimensional ratio, 0.960 or more are more preferable, 0.993 or less are more preferable, respectively, and, as for the upper limit, 0.990 or less are more preferable.

If the dimensional ratio is less than 0.920, the solid material attached to the aperture or the screw of the container and dried and precipitated may require a considerable force to close the lid or to detach the lid or the intermediate plug, which may significantly reduce workability. There is. On the other hand, when the dimensional ratio exceeds 0.995, the sealing property of the container is lowered, so that the low boiling point solvent contained in the nonaqueous electrolyte is easily volatilized, or moisture is easily mixed from the outside of the container, so that the quality of the nonaqueous electrolyte is long-term. There is a possibility that I cannot keep it.

The material of the lid and the intermediate plug is not particularly limited as long as the components of the material do not elute at a degree of being temporarily in contact with the nonaqueous electrolyte, and the material has a sealing property and durability as the lid or the intermediate plug, and resins and metal materials can be used. . Among them, from the viewpoint of airtightness and handleability, the lid is preferably made of a relatively hard, high mechanical strength synthetic resin such as a polypropylene resin and a high density polyethylene resin.

Since the intermediate plug usually hardly comes into contact with the nonaqueous electrolyte which is the contents of the container, the material of the intermediate plug is hardly eluted with the nonaqueous electrolytic solution as compared with the elution of the container material into the nonaqueous electrolyte. For this reason, the intermediate plug is made of polyethylene resins such as low density polyethylene (LDPE) and linear low density polyethylene (LLDPE), polytetrafluoroethylene (PTFE), and tetrafluoroethylene purple from the viewpoint of sealing properties, durability and handling properties. Luoroalkylvinylether copolymer (PFA), tetrafluoroethylene hexafluoropropylene copolymer (FEP), tetrafluoroethylene ethylene copolymer (ETFE), polyvinylidene fluoride (PVDF), poly Preferred are synthetic resins having a smaller mechanical strength and relatively softer than synthetic resins used for lids made of fluorine resins such as chlorotrifluoroethylene (PCTFE).

The capacity of the container is not particularly limited, but from the viewpoint of handleability, 10 to 200,000 cm ³ is preferable, 20 to 30,000 cm ³ is more preferable, 50 to 1,000 cm ³ is more preferable, and 100 to 500 cm ³ is particularly preferable. Do. Although the trunk diameter of a container is not specifically limited, From a viewpoint of handleability, 50-150 mm is preferable and 60-100 mm is more preferable.

When filling a nonaqueous electrolyte in a container, 20 to 98% of the capacity of the container is preferable, as for the filling rate, 30 to 97% is more preferable, and 50 to 95% is still more preferable. When the filling rate is less than 20%, the low boiling point solvent in the nonaqueous electrolyte is likely to volatilize, and the concentration of the high boiling point solvent is increased, so that solids tend to precipitate in the caliber and the screw, so that the sealing property may be lowered. On the other hand, when the filling rate exceeds 98%, the lid may easily come into contact with the nonaqueous electrolyte, or the internal pressure in the container may increase, leading to a decrease in hermeticity. Therefore, the range of said filling rate is preferable. In addition, it is preferable to fill the upper surface of the nonaqueous electrolyte to be filled to be 1 cm or more, more preferably 2 cm or more, and even more preferably 3 cm or more, lower than the pouring hole.

[Non-aqueous solvent]

Examples of the nonaqueous solvent used in the nonaqueous electrolyte of the present invention include cyclic carbonates, chain esters, lactones, ethers, amides, nitriles, phosphate esters, S═O bond-containing compounds, carboxylic anhydrides and aromatic compounds.

From the viewpoint of exhibiting the effects of the present invention more effectively, the nonaqueous solvent preferably contains a cyclic carbonate, and more preferably contains a cyclic carbonate and a chain ester.

On the other hand, the term "chain ester" is a concept containing a chain carbonate and a chain carboxylic acid ester.

A nonaqueous solvent can be used individually by 1 type or in combination of 2 or more type.

(Cyclic carbonate)

Examples of the cyclic carbonate include ethylene carbonate (EC), propylene carbonate (PC), 1,2-butylene carbonate, 2,3-butylene carbonate, 4-fluoro-1,3-dioxolane-2-one (FEC ), Trans or cis-4,5-difluoro-1,3-dioxolane-2-one (hereinafter collectively referred to as "DFEC"), vinylene carbonate (VC), vinyl ethylene carbonate ( VEC) etc. are mentioned suitably.

Among these, cyclic carbonates containing at least one member selected from EC, PC, and a cyclic carbonate containing a double bond or a fluorine atom are preferable, and a cyclic ring containing EC and / or PC and a double bond or a fluorine atom is preferable. The use of one or more carbonates is more preferable because the battery characteristics are further improved, and it is particularly preferable to include both cyclic carbonates containing a double bond and EC and / or PC, and a cyclic carbonate containing a fluorine atom. Do. As cyclic carbonate containing a double bond, VC and VEC are preferable, and as cyclic carbonate containing a fluorine atom, FEC and DFEC are preferable.

Specific examples of preferred combinations of these cyclic carbonates include EC and VC, FEC and PC, DFEC and PC, EC and FEC and PC, EC and FEC and VC, EC and VC and VEC.

Although content of cyclic carbonate is not specifically limited, It is preferable to use in the range of 0-40 volume% of the total volume of a nonaqueous solvent. Since the viscosity of a nonaqueous electrolyte may rise when the said content exceeds 40 volume%, it is preferable that it is the said range.

(Chip ester)

Examples of chain esters include asymmetric chain carbonates such as methyl ethyl carbonate (MEC), methyl propyl carbonate, methyl isopropyl carbonate, methyl butyl carbonate and ethyl propyl carbonate, dimethyl carbonate (DMC), diethyl carbonate (DEC) and dipropyl carbonate. , Symmetrical linear carbonates such as dibutyl carbonate, methyl acetate, ethyl acetate, methyl propionate, ethyl propionate, methyl pivalate, butyl butyl volatiles, hexyl pivalate, octyl pivalate, dimethyl oxalate, ethyl methyl oxalate, dioxalate, etc. The linear carboxylic acid ester of can be mentioned.

In particular, when asymmetric linear carbonate is included, battery characteristics such as storage characteristics tend to be improved, and it is also preferable to use asymmetric linear carbonate and symmetric linear carbonate in combination. Moreover, it is preferable that the ratio of the asymmetrical linear carbonate contained in a linear carbonate is 50 volume% or more. As an asymmetric linear carbonate, what has a methyl group is preferable, and MEC is more preferable.

Although content of a chain ester, especially a chain carbonate is not specifically limited, It is preferable to use in the range of 60-100 volume% with respect to the total volume of a nonaqueous solvent. Since the viscosity of a nonaqueous electrolyte may rise that the said content is less than 60 volume%, it is preferable that it is the said range.

The ratio of the cyclic carbonate and the chain ester (chain carbonate) is preferably 10:90 to 40:60 of the cyclic carbonate: chain ester (chain carbonate) (volume ratio) from the viewpoint of improving battery characteristics such as storage characteristics. : 85-35: 65 are more preferable, and 20: 80-30: 70 are still more preferable.

(Other nonaqueous solvents)

As lactone, (gamma) -butyrolactone (GBL), (gamma) -valerolactone, (alpha)-angelica lactone, etc. are mentioned, As an ether, tetrahydrofuran, 2-methyl tetrahydrofuran, 1, 3- dioxolane, Cyclic ethers such as 1,3-dioxane and 1,4-dioxane, chains such as 1,2-dimethoxyethane (DME), 1,2-diethoxyethane and 1,2-dibutoxyethane And ethers. Examples of the amide include dimethylformamide and the like, and nitriles include acetonitrile, propionitrile, succinonitrile, glutaronitrile, adiponitril, and pimelonite. And a reel. Examples of the phosphate ester include trimethyl phosphate, tributyl phosphate, and trioctyl phosphate.

Examples of the S = O bond-containing compound include sultone compounds such as 1,3-propanesultone, 1,3-butanesultone and 1,4-butanesultone, among ethylene sulfite and 1,2-cyclohexanediol Cyclic sulfite compounds such as click sulfite, 5-vinyl-hexahydro-1,3,2-benzodioxathiol-2-oxide, 1,2-ethanedinol dimethanesulfonate, 1,2- Propanediol dimethanesulfonate, 1,3-propanediol dimethanesulfonate, 1,4-butanediol dimethanesulfonate, 1,5-pentanediol dimethanesulfo Sulfonic acid ester compounds such as nate and methanesulfonic acid 2-propynyl, vinylsulfone compounds such as divinylsulfone, 1,2-bis (vinylsulfonyl) ether, and bis (2-vinylsulfonylethyl) ether, sulfolane Etc. can be mentioned.

Examples of the carboxylic acid anhydride include cyclic carboxylic acid anhydrides such as acetic anhydride and propionic anhydride, cyclic carboxylic anhydrides such as succinic anhydride, maleic anhydride, glutaric anhydride, and itaconic anhydride.

Examples of the aromatic compound include cyclohexylbenzene, fluorocyclohexylbenzene compound (1-fluoro-2-cyclohexylbenzene, 1-fluoro-3-cyclohexylbenzene, 1-fluoro-4-cyclohexylbenzene), tert Aromatic compounds having a branched alkyl group such as -butylbenzene, tert-amylbenzene, and 1-fluoro-4-tert-butylbenzene; biphenyl, terphenyl (o-, m-, p-form), diphenyl Tertiary hydrides (1,2-dicyclohexylbenzene), fluorobenzene, difluorobenzene (o-, m-, p-form), anisole, 2,4-difluoroanisole, terphenyl And aromatic compounds such as 2-phenylbicyclohexyl, 1,2-diphenylcyclohexane and o-cyclohexylbiphenyl).

Among the above-mentioned, especially when the solvent which is a solid at normal temperature is contained, since the effect of this invention is easy to be exhibited further, it is preferable, and especially it is more preferable if ethylene carbonate and / or vinylene carbonate are contained.

[Electrolyte salt]

As an electrolyte salt used for this invention, the following lithium salt and onium salt are mentioned suitably.

(Lithium salt)

Examples of the lithium salt include inorganic lithium salts such as LiPF ₆ , LiPO ₂ F ₂ , Li ₂ PO ₃ F, LiBF ₄ , and LiClO ₄ , LiN (SO ₂ CF ₃ ) ₂ , LiN (SO ₂ C ₂ F ₅ ) ₂ , and LiCF. ₃ SO ₃ , LiC (SO ₂ CF ₃ ) ₃ , LiPF ₄ (CF ₃ ) ₂ , LiPF ₃ (C ₂ F ₅ ) ₃ , LiPF ₃ (CF ₃ ) ₃ , LiPF ₃ (iso-C ₃ F ₇ ) ₃ , A lithium salt containing a chain alkyl fluoride group such as LiPF ₅ (iso-C ₃ F ₇ ), or a ring such as (CF ₂ ) ₂ (SO ₂ ) ₂ NLi, (CF ₂ ) ₃ (SO ₂ ) ₂ NLi Lithium salts having an alkylene fluoride chain, and lithium salts having an oxalate complex such as bis [oxalate-O, O '] lithium borate or difluoro [oxalate-O, O'] lithium borate as an anion; These can be mentioned, and these 1 type or in mixture of 2 or more types can be used. Among these, at least one selected from LiPF ₆ , LiPO ₂ F ₂ , Li ₂ PO ₃ F, LiBF ₄ , LiN (SO ₂ CF ₃ ) _2, and LiN (SO ₂ C ₂ F ₅ ) ₂ is preferable, and LiPF ₆ , LiPO ₂ F _2, LiBF ₄ and LiN (SO ₂ CF ₃₎ and more preferably at least one member selected from the _second.

(Onium salt)

As onium salt, the various salt which combined the onium cation and anion shown below are mentioned suitably.

Specific examples of onium cations include tetramethylammonium cations, ethyltrimethylammonium cations, diethyldimethylammonium cations, triethylmethylammonium cations, tetraethylammonium cations, N, N-dimethylpyrrolidinium cations, N-ethyl- (N, N ') - bipyrrolidinium cation, N, N'-dimethylimidazolinium cation, N, N'-dimethylpyrrolidinium cation, Ethyl-N'-methylimidazolium cation, N, N'-diethylimidazolium cation, N, N'-dimethylimidazolium cation, N-ethyl- N, N'-diethylimidazolium cation, and the like.

A specific example of the anionic examples, PF ₆ anion, BF ₄ anion, ClO ₄ anions, AsF ₆ anion, CF ₃ SO _{3 anion, N (CF 3 SO 2)} 2 _{anions, N (C 2 F 5 SO} 2) 2 anions such as Can be suitably selected.

These electrolyte salts can be used individually by 1 type or in combination of 2 or more types.

Among the above-mentioned, especially when electrolyte salt which is solid at normal temperature is contained, since the effect of this invention is more easy to be exhibited, it is preferable, and among these, at least 1 sort (s) chosen from LiPF ₆ , LiPO ₂ F _2, and LiBF ₄ is contained. If present, the electrolyte salt is more preferable because it tends to react with water and deposit deposits easily on the aperture of the container.

0.3 M or more is preferable, as for the minimum of the density | concentration when electrolyte salt melt | dissolves in a non-aqueous electrolyte solution, 0.5 M or more is more preferable, 0.8 M or more is more preferable. In addition, although the upper limit changes with kinds of electrolyte salt and combination of nonaqueous solvent, it can be used until the density | concentration of electrolyte salt reaches saturation with respect to a nonaqueous solvent. 4M or less is preferable, as for the upper limit, 3M or less is more preferable, and 2M or less is more preferable.

[Non-aqueous electrolytic solution]

The nonaqueous electrolyte of the present invention is a nonaqueous electrolyte in which a nonaqueous electrolyte in which an electrolyte salt is dissolved in a nonaqueous solvent is filled in a container, wherein the container is made of aluminum or an aluminum alloy, and the lid and the middle cap of the container are made of resin. It is a nonaqueous electrolyte solution contained in the container in which the water content of the nonaqueous electrolyte solution 30 days after the said container storage is maintained at 50 ppm or less.

This non-aqueous electrolyte solution can be obtained by dissolving the electrolyte salt in 0.3 M or more and 4 M or less in the non-aqueous solvent, for example.

At this time, it is preferable to refine | purify the compound added to the nonaqueous solvent and nonaqueous electrolyte used beforehand in the range which does not reduce a productivity notably, and to use what has very few impurities.

(Moisture of nonaqueous electrolyte)

In the present invention, the water content of the nonaqueous electrolyte solution at the time of container storage is preferably adjusted in advance so as to be kept at 50 ppm or less, more preferably 30 ppm or less, more preferably 25 ppm or less, even more preferably 15 ppm or less.

The water content of the non-aqueous electrolyte solution after 30 days of container storage becomes like this. Preferably it is 50 ppm or less, More preferably, it is 40 ppm or less, More preferably, it is 25 ppm or less, Especially preferably, it is 15 ppm or less, and it adjusts previously.

The water content of the nonaqueous electrolyte solution after 60 days of container storage is preferably adjusted in advance so as to be maintained at 50 ppm or less, more preferably 40 ppm or less, more preferably 25 ppm or less, and still more preferably 15 ppm or less.

The water content of the nonaqueous electrolyte solution after 180 days of container storage is preferably 50 ppm or less, more preferably 40 ppm or less, still more preferably 25 ppm or less, and particularly preferably 15 ppm or less.

In addition, the moisture of a nonaqueous electrolyte solution can be measured by the Karl-Fischer moisture measuring apparatus.

The change in the water content of the nonaqueous electrolyte from the time of container storage of the nonaqueous electrolyte to 30 days after storage is ± 15 ppm, preferably ± 10 ppm, and more preferably maintained at ± 5 ppm.

In addition, the change of the moisture content of the nonaqueous electrolyte from the time of storing the container of the nonaqueous electrolyte to 60 days after the storage is preferably maintained at ± 20 ppm, more preferably at ± 15 ppm, even more preferably at ± 10 ppm.

The change in the water content of the nonaqueous electrolyte from the time of container storage of the nonaqueous electrolyte to after 180 days of storage is preferably maintained at ± 30 ppm, more preferably at ± 20 ppm, even more preferably at ± 10 ppm.

(Acid content of nonaqueous electrolyte)

The acid content of the non-aqueous electrolyte solution at the time of container storage is preferably 100 ppm or less, more preferably 50 ppm or less, still more preferably 30 ppm or less, particularly preferably 25 ppm or less in terms of hydrogen fluoride (HF).

The acid content of the non-aqueous electrolyte solution 30 days after storage from storage is preferably 100 ppm or less, more preferably 50 ppm or less, still more preferably 30 ppm or less, and particularly preferably 25 ppm or less in terms of HF.

The acid content of the non-aqueous electrolyte solution after 60 days of container storage is preferably 100 ppm or less, more preferably 50 ppm or less, still more preferably 30 ppm or less, particularly preferably 25 ppm or less in terms of HF.

The acid content of the non-aqueous electrolyte solution after 180 days of container storage is preferably 100 ppm or less in terms of HF, more preferably 50 ppm or less, still more preferably 30 ppm or less, and particularly preferably 25 ppm or less.

The change in the acid content of the nonaqueous electrolyte from the time of container storage of the nonaqueous electrolyte to 30 days after the storage is preferably ± 20 ppm, more preferably ± 15 ppm, still more preferably ± 10 ppm, particularly preferably ± 5 ppm.

In addition, the measurement of the acid content of a non-aqueous electrolyte solution uses 0.01N-NaOH aqueous solution as a titration solution and bromothymol blue (BTB) liquid as an indicator, for example, the automatic titration apparatus (brand name: TS-980) made by Hiranuma Industrial Co., Ltd. It can measure using, and can make acid value the value which converted the measured value into HF.

(APHA of nonaqueous electrolyte)

APHA of the non-aqueous electrolyte solution at the time of container storage becomes like this. Preferably it is 150 or less, Preferably it is 100 or less, More preferably, it is 50 or less, More preferably, it is 30 or less.

The Hazen unit color number (APHA) of the non-aqueous electrolyte solution 30 days after storage of the container of the non-aqueous electrolyte solution is preferably 150 or less, more preferably 100 or less, more preferably 50 or less, further preferably 30 or less.

Moreover, APHA of the nonaqueous electrolyte solution 60 days after container storage becomes like this. Preferably it is 150 or less, Preferably it is 100 or less, More preferably, it is 50 or less, More preferably, it is 30 or less.

Moreover, APHA of the nonaqueous electrolyte solution 180 days after container storage becomes like this. Preferably it is 150 or less, Preferably it is 100 or less, More preferably, it is 50 or less, More preferably, it is 30 or less.

In addition, the measurement of APHA calculated | required the standard liquid of the density | concentration closest to a sample based on JISK-6901, and made the standard liquid number the APHA value.

[Preservation method of nonaqueous electrolyte solution]

The storage method of the non-aqueous electrolyte solution of this invention is a storage method of the non-aqueous electrolyte solution which preserves a non-aqueous electrolyte solution in a container, Comprising: The said container is comprised from aluminum or an aluminum alloy, The lid and intermediate stopper of the said container are resin-made, The said container The water content of the nonaqueous electrolyte solution after 30 days of storage is maintained at 50 ppm or less.

From the viewpoint of corrosion inhibition, the temperature at the time of storage of the nonaqueous electrolyte solution is preferably 0 ° C to 60 ° C, more preferably 10 ° C to 50 ° C, further preferably 20 ° C to 45 ° C.

Other details are as described above.

[Use of nonaqueous electrolyte solution]

The nonaqueous electrolyte of the present invention is a lithium battery (lithium primary battery and lithium secondary battery), an electric double layer capacitor (an electrochemical device that stores energy by using an electric double layer capacity of an electrolyte and an electrode interface), and doping of an electrode. Electrochemical devices, such as electrochemical devices that store energy using dedoping / dedoping reactions, and lithium ion capacitors (electrochemical devices that store energy using intercalation of lithium ions onto carbon materials, such as graphite as cathodes). It can be used as a nonaqueous electrolyte solution. The nonaqueous electrolyte of the present invention can also be used for solid polymer electrolytes.

Among these, it is preferable to use as a 1st electrochemical element (namely, for a lithium battery), and to use as a lithium secondary battery is the most suitable.

Example

Although the Example of this invention is shown below, this invention is not limited to these Examples.

Preparation Example 1 (Preparation of Non-Aqueous Electrolyte)

A nonaqueous solvent of ethylene carbonate (EC): methyl ethyl carbonate (MEC) (volume ratio) = 3: 7 was prepared, and LiPF ₆ was dissolved therein so as to have a concentration of 1 M as an electrolyte salt, thereby preparing a nonaqueous electrolyte solution.

Example 1

The nonaqueous electrolyte obtained in Preparation Example 1 was placed in a 1000 cm ³ container made of aluminum (JIS 1050) with a purity of 99.5% (the lid is made of polypropylene resin, the middle plug is made of low density polyethylene, the inner diameter of the injection hole is 28.0 mm, and the outer diameter of the inner middle plug is 29.0 mm), and it preserve | saved for 180 days at 25 degreeC, and measured the moisture and acid content of a nonaqueous electrolyte solution with time by the said method before storage. The results are shown in Table 1.

Example 2

In Example 1, operation similar to Example 1 was performed except having changed the storage temperature into 40 degreeC. The results are shown in Table 1.

Example 3

The same operation as in Example 1 was carried out except that 1,3-propanesultone was added to the nonaqueous electrolyte solution in the nonaqueous electrolyte solution to prepare a nonaqueous electrolyte solution. The results are shown in Table 1.

Comparative Examples 1 and 2

In Example 1, operation similar to Example 1 was performed except having changed the preservation container into the stainless steel (made by Wada Stainless Co., Ltd., 1000 cm <^3> ) and the polypropylene (PP) product (made by As One Co., Ltd., 1000 cm <^3> ), respectively. . The results are shown in Table 1.

The nonaqueous electrolyte preserved under the conditions of Examples 1 and 2 maintained good quality without involving the elution of the container material, and the performance of the lithium secondary battery using the stored nonaqueous electrolyte did not impair electrochemical properties at all. . Moreover, since the weight reduction of the container was aimed at, the handleability of the container was also remarkably improved. In contrast, Comparative Example 1 has a container mass of 6.5 times the container of the present invention, and handling is inferior to the containers of Examples 1 and 2.

Moreover, in the nonaqueous electrolyte solution preserve | saved on the conditions of the comparative example 2, the material of a container eluted in electrolyte solution, and when UV of electrolyte solution was measured with the spectrophotometer (UV2400PC, the Shimadzu Corporation make), it originates in the additive component of an aromatic system. UV peaks were detected. The amount of elution increased with days, and the electrochemical performance of the lithium secondary battery using the preserved nonaqueous electrolyte was also affected.

Examples 4-9 and Comparative Example 3

(1) operation 1

As the nonaqueous solvent component, ethylene carbonate (EC), vinylene carbonate (VC), methyl ethyl carbonate (MEC), γ-butyrolactone (GBL), and 1,2-dimethoxyethane (DME) are prepared, and an electrolyte is prepared. LiPF ₆ and LiBF ₄ were prepared as a salt, and the nonaqueous electrolyte solution of the composition shown in Table 2 was prepared.

A glove box in which a container made of aluminum (JIS 1050) with a purity of 99.5% (inner volume of 1000 cm ³ , the inner diameter of the injection hole is 28.0 mm) or stainless steel (made by Wada Stainless Co., Ltd., 1000 cm ³ ) has a dew point of -60 ° C. or less. Pour 900 mL or 400 mL of non-aqueous electrolyte solution of various compositions into it, and place a middle stopper made of polyethylene (PE) (an inner stopper having an outer diameter of 29.0 mm or 28.3 mm, or an outer stopper having an inner diameter of 31.0 mm, except for a stainless container). The intermediate plug was not used) and tightly enclosed using a polypropylene (PP) cap or a stainless cap. Immediately thereafter, the lid and the intermediate cap were opened, and the nonaqueous electrolyte solution in the container was collected by a pipette to measure the HF concentration, the H ₂ O concentration, and the APHA in the nonaqueous electrolyte solution. The results are shown in Table 2.

(2) Operation 2 [assuming case when electrolyte overflows]

About 1 mL of the nonaqueous electrolyte is collected, and the electrolyte is attached to the periphery of the threaded portion of the aluminum container or the stainless container, and then wiped off with a cloth, and the intermediate plug is used (but the intermediate plug is not used for the stainless container). After tightly encapsulating with a lid, the aluminum container or the stainless container was taken out of the glove box and stored in a constant temperature and humidity chamber at 60 ° C for 40% humidity for one week. Thereafter, the aluminum container or the stainless container is put back into the glove box, and immediately the lid and the intermediate cap (but the intermediate cap is not used for the stainless container) are opened, and the nonaqueous electrolyte in the container is taken out, HF concentration, H ₂ O concentration, and APHA in the electrolyte solution were measured. At this time, 1 mL of nonaqueous electrolyte solution was attached to the screw part, and the operation of wiping was performed.

Then, the said operation 2 was repeated 2 times further. The results are shown in Table 2.

In Table 2, the opening and closing level of the lid was evaluated based on the following criteria.

Level 1: Can be opened and closed by hand without difficulty.

Level 2: Requires strength but can be opened and closed by hand.

Level 3: It became difficult to open and close by hand, using a tool to open and close.

Analysis of the solid adhering to the outer circumference of the screw portion of the container of Comparative Example 3 showed that the solid was a mixture of decomposed product, ethylene carbonate, and vinylene carbonate, which are believed to be derived from LiPF ₆ or LiBF ₄ .

From Table 2, the nonaqueous electrolyte solution stored in the aluminum container of Examples 4-9 of this invention has a low rise of the moisture and acid content in a nonaqueous electrolyte solution compared with the nonaqueous electrolyte solution stored in the stainless container of the comparative example 3, and a coloring degree You can see little.

Electrolyte solution containing a lithium salt such as LiPF ₆ or a component that becomes a solid at room temperature such as ethylene carbonate increases the fixed matters in the bore of the container, and the sealing property is lowered, so that the lithium salt reacts with the water penetrated into the container. Acid content (HF) is produced or colored. Moreover, opening and closing of a lid tends to be difficult by the said fixed substance. However, when the aluminum container of the present invention was used, there was no increase in moisture or HF concentration in the electrolyte solution, and coloration was difficult, and it did not interfere with opening and closing of the lid and the intermediate plug, and the handleability was good.

Also, the shape of the container body of Example 4 was changed from a bottle type to an aluminum laminated paper bag type or aluminum pouch type container, and the same polypropylene lid as in Example 4 and the inner inner stopper made of polyethylene were almost the same. Effect is obtained.

According to the container for nonaqueous electrolyte solution of this invention and the storage method of a nonaqueous electrolyte solution, since a nonaqueous electrolyte solution can be easily maintained at high quality, it is very useful for storage and use of a nonaqueous electrolyte solution.

1: can body (bottle type) 2: can body
3: injection hole 4: skirt wall
5: caliber 6: thread
7: internal intermediate plug 8: external intermediate plug
9: Lid with an annular projection (middle stopper)

Claims (13)

A container made of a material containing an aluminum or aluminum alloy layer, and filled with a nonaqueous electrolyte in which an electrolyte salt is dissolved in a nonaqueous solvent, the container having a resin lid and an intermediate cap, and storing the container. A container for nonaqueous electrolytes, which maintains the water content of the nonaqueous electrolyte solution after 30 days to 50 ppm or less. The method according to claim 1,
A container for nonaqueous electrolyte consisting of aluminum or aluminum-manganese alloy with a purity of 99% or higher. The method according to claim 1,
A container for nonaqueous electrolyte, wherein the lid is made of polypropylene resin and the middle plug is made of polyethylene resin. The method according to claim 1,
A container for a nonaqueous electrolyte having a ratio of (inner diameter of the injection hole / outer diameter of the intermediate plug), or a ratio of (inner diameter of the injection hole / outer diameter of the injection hole) of 0.920 to 0.995. A nonaqueous electrolyte in which a nonaqueous electrolyte solution in which an electrolyte salt is dissolved in a nonaqueous solvent is filled into a container, wherein the container is made of a material containing an aluminum or aluminum alloy layer, and the lid and the middle cap of the container are made of resin. The nonaqueous electrolyte solution contained in the container whose water content of the nonaqueous electrolyte solution after 30 days of preservation is maintained at 50 ppm or less. 6. The method of claim 5,
The non-aqueous electrolyte solution contained in the container whose acid content of the non-aqueous electrolyte solution 30 days after container storage is 100 ppm or less in conversion of hydrogen fluoride (HF). 6. The method of claim 5,
Non-aqueous electrolyte in a container whose change in acid content of the non-aqueous electrolyte until 30 days after container storage is within ± 20 ppm in terms of HF. 6. The method of claim 5,
The nonaqueous electrolyte in a container whose APHA of a nonaqueous electrolyte is 150 or less. 6. The method of claim 5,
The nonaqueous electrolyte solution contained in the container whose nonaqueous solvent contains cyclic carbonate. 6. The method of claim 5,
The nonaqueous electrolyte solution in which the nonaqueous solvent contains cyclic carbonate and chain ester. 6. The method of claim 5,
Non-aqueous container in which the electrolyte salt is at least one selected from LiPF ₆ , LiPO ₂ F ₂ , Li ₂ PO ₃ F, LiBF ₄ , LiN (SO ₂ CF ₃ ) ₂ and LiN (SO ₂ C ₂ F ₅ ) ₂ Electrolyte solution. 6. The method of claim 5,
A nonaqueous electrolyte solution in which the nonaqueous solvent contains ethylene carbonate and the electrolyte salt is LiPF ₆ . A nonaqueous electrolyte preservation method for storing a nonaqueous electrolyte in a container, wherein the container is made of a material containing an aluminum or aluminum alloy layer, and the lid and the middle cap of the container are made of resin, and the nonaqueous solution 30 days after the container is stored. The storage method of a nonaqueous electrolyte solution which keeps the moisture content of electrolyte solution at 50 ppm or less.

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